Zebrafish Study Points to Genetic Drivers of Back Pain

Zebrafish Models Reveal Genetic Drivers of Spinal Disc Degeneration

Back pain affects most individuals at some point in their lives. A primary underlying cause is intervertebral disc degeneration, or IVDD, which involves the gradual breakdown of the spinal discs that cushion the bones of the spine. Despite how common and costly the condition is, there are currently no medicines capable of stopping or reversing IVDD, leaving surgery as the only long-term treatment option.

Genetics are known to play a significant role in the development of the condition. A gene connected to a protein called collagen IX—which helps hold the structural fibers of spinal discs together—has been repeatedly linked to early-onset disc problems.

Uncovering Genetic Faults and Cellular Pathways

To better understand how genetic faults lead to disc disease, scientists from the Universities of Edinburgh and Bristol studied zebrafish bred to lack a working copy of the collagen-linked gene. As the fish aged, their spines developed problems strikingly similar to human disc disease, with spinal bones fusing together and the tissue between vertebrae becoming abnormally hardened by mineral deposits.

According to researchers, this hardening followed the breakdown of a supportive scaffold layer in the developing spine well before minerals began to accumulate. By examining which genes were switched on or off in the fish, the team identified changes in fat metabolism and mTOR, a biological pathway controlling cell growth and nutrient response. They also found disruptions in phosphate handling and vitamin A signaling that correlate with mineral accumulation.

The research was supported by Arthritis UK and the Biotechnology and Biological Sciences Research Council. Dr. Caroline Aylott, head of research delivery at Health Tech World, noted that back pain has blighted millions over generations and that the work brings fresh hope for 9.5 million people living with the condition across the U.K.

Potential Treatments and Future Drug Targets

The research team successfully demonstrated ways to reduce the damage observed in the zebrafish models. A bone-protecting medicine known as a bisphosphonate, which is already used to treat osteoporosis, successfully blocked mineral deposits from forming. Additionally, restricting the fish’s food intake and using medicines that dampen fat metabolism lowered the number of spinal fusions.

The findings point to phosphate handling and fat metabolism as promising targets for future therapeutics. Dr. Erika Kague, study lead from the University of Edinburgh’s Institute of Genetics and Cancer, emphasized the significance of the findings for a field long dependent on surgery.

For decades, surgery has been the only real answer for disc disease, Dr. Kague said. By understanding the biology that drives the spine to harden, our zebrafish studies point to several ways of slowing it down, including a drug already used safely in patients. There’s more work to do, but for a condition that’s affected people for generations without a treatment in sight, this is super exciting.